Marked Tree WWTP - Secondary Treatment Plant in Marked Tree, Arkansas

Marked Tree WWTP is a municipal wastewater treatment facility located on Black Oak Road in Marked Tree, Arkansas, a small town in Poinsett County. The plant serves a population of approximately 2,566 residents, consistent with a small community-scale operation in the rural Mississippi Delta region. The plant provides secondary treatment, the standard biological process required by the U.S. Clean Water Act for municipal wastewater. With a designed capacity of 1,589.87 cubic meters per day and an average discharge volume of 916.07 cubic meters per day, the facility operates well within its capacity. Under the National Pollutant Discharge Elimination System (NPDES), plants of this size must meet effluent limits for biochemical oxygen demand, total suspended solids, and other parameters to protect receiving waters. Treated effluent from Marked Tree WWTP flows into local streams that are part of the St. Francis River basin, which ultimately drains into the Mississippi River. The Mississippi River system supports diverse aquatic life and provides drinking water for millions downstream. The plant's secondary treatment helps reduce nutrient and organic pollutant loads, contributing to the ecological health of this major river system.

The plant discharges into the St. Francis River watershed, a tributary of the Mississippi River. The Mississippi River is a critical ecological corridor for fish, migratory birds, and other wildlife. Nutrient loading from wastewater can contribute to the Gulf of Mexico hypoxic zone, making effective treatment important for downstream water quality.